A catheter which can perform a bending operation on a distal portion by pulling an operation wire has been proposed. In a case of inserting this kind of catheter into a lumen in a living body such as a blood vessel, it is possible to select the insertion direction by bending the distal portion at a branch point of the lumen in a living body. In a case of a catheter with a comparatively large diameter, it is possible to bend the distal portion of the catheter in one direction by pushing a wire which has a large width and is used as an operation wire. In contrast, it is possible to bend the distal portion thereof in the other direction by drawing this wire.
In contrast, in a case of a catheter with a comparatively small diameter, in particular, a micro-catheter which has a small diameter and can be inserted into a peripheral blood vessel, an operation wire is extremely thin. Therefore, it is impossible to bend a distal portion even if the operation wire is pushed. This is because, even if the extremely thin operation wire is pushed, the extremely thin operation wire bends easily, and as a result, buckles, and therefore, it is impossible to transmit a sufficient pushing force to bend the distal portion of the catheter. Accordingly, in the case of a catheter such as a micro-catheter which has a small diameter, a distal portion of the catheter is bent by, in general, providing a plurality of operation wires arranged to face each other, and by selecting and pulling an operation wire positioned in a direction toward which bending is required, and loosening another operation wire so as to bend the pulled operation wire to the inside.
For this reason, in a catheter provided with a plurality of operation wires, in general, a turning operation is performed using an operation panel called a reel, a wheel, or the like so as to pull one operation wire, and at the same time, to loosen another operation wire.
As this kind of catheter, the following Patent document 1 is exemplified.
In Patent document 1, a catheter which has an adjustment function of adjusting the drawable amount of an operation wire in an initial state is disclosed in addition to the operation panel which pulls the operation wire as described above.